CV Drugs 1 Flashcards
(30 cards)
what is the MOA of methylxanthines?
Phosphodiesterase inhibition > inc. amounts of cAMP > inc. release of ENDOGENOUS epinephrine
T/F: methylxanthines are cardiac stimulants
TRUE, include aminophylline and theophylline
what is the main effect of methylxanthines?
bronchodilation! direct relaxation of smooth m. in bronchi and pulmonary vasculature
what type of arrhythmia are methylxanthines occasionally used for?
bradyarrhythmias i.e. AV block
in what situation are methylxanthines contraindicated?
patients with severe cardiac disease or hypertensions (risk tachycardia, worsen tachyarrhythmias)
T/F: methylxanthines induce diuresis making them cardiac diuretics
TRUE
what is the major difference between aminophylline and theophylline?
aminophylline is the parenteral form of theophylline
what is the most commonly used catecholamine for CHF due to myocardial failure?
dobutamine = B-1 agonist
what might occur if you use methylxanthines with a severely hypoxic patient?
you may worsen V/Q mismatch
what is a cardiac stimulant that is also one of the drugs of choice for treatment of calcium channel blocker toxicity?
glucagon
what cardiac stimulant is one of the drugs of choice for emergency treatment of hyperkalemia?
calcium salts
what categories of drugs would you use for pharmacologic therapy of CHF?
- inotropes
- vasodilators
- inodilators
- diuretics
- beta-blockers
what adjunctive therapy can you do in addition to pharmacologic therapy for CHF?
- sodium-restricted diet
- exercise restriction
- oxygen therapy
T/F: digoxin is used extra-label and is a cardiac stimulant
FALSE, digoxin is a positive inotropic drug
what kind of metabolism does digoxin undergo?
enterohepatic recirculation
T/F: digoxin is excreted mainly in renal in cats and renal and hepatic in dogs and horses
FALSE, opposite
what sort of renal effect do you see with the use of digoxin?
= cardiac diuretic, secondary to increased CO
T/F: acute use in digoxin will result in HYPERkalemia while chronic use will result in HYPOkalemia
TRUE
what is the number one adverse effect of digoxin?
GI signs ( irritation, vomiting, nausea, anorexia, diarrhea)
what type of digoxin-induced arrythmias are possible?
TACHYarrhythmias
what is the specific antidote for digoxin toxicity?
digoxin immune Fab (Digibind)
what drug can you use if you have digoxin toxicity and want to decrease enterohepatic recirculation?
cholestyramine
what are the two clinical uses for digoxin?
CHF and atrial fibrillation or flutter
besides serving as a positive inotrope what other major effect does pimobendan have?
vasodilator! = PDE III inhibitor which results in arterial and venous dilation (reduced preload and afterload)
